Such a device is known from EP 0 806 597 A1. The previously known device provided for linking two end pieces of a fluid line system has a casing part into which an inner part and a loose sealing ring that serves as a sealing unit can be introduced. When a first end piece that is configured with a sealing flange on the end is inserted via a first introduction area, longitudinal tongues of the casing part are pressed outward and the loose sealing ring comes to rest between the sealing flange and a face of the inner part, whereby the sealing flange is arranged between an inwardly pointing inner bead of the casing part and an outwardly pointing ring collar of the inner part. In this arrangement of the first end piece, the inner part is fixed, whereby a securing ring is slipped around the longitudinal tongues in the first introduction area in order to prevent the first end piece from slipping out unintentionally.
The inner part exhibits two springy arms which have lugs that project outward and which come into engagement with the ring bead when a second end piece configured with a ring bead is inserted into a second introduction area. Configured on the casing part are retaining fingers which, with proper arranging of the end piece configured with the ring bead, engage behind the ring bead and fix the second end piece. In this position, the lugs project beyond the outside of the casing part and by doing so, they indicate the proper arranging of the second end piece. With the previous device, although the provision of the lugs made it easy to see whether the second end piece is properly arranged, the linking of the end pieces is still relatively cumbersome.
The invention is based on the problem of suggesting a device of the type described above which is distinguished by a relatively simple and reliable linking of the end pieces, and with which the danger of the loss of the sealing unit is as good as impossible.